This invention relates generally to the conversion of electrical power into mechanical power in the form of high-torque rotary motion, and more particularly in the use of magnetostriction to accomplish such purpose.
Magnetostriction motors are generally well known in the art and involve the use of an active magnetostrictive body such as an elongated rod which undergoes dimensional change when magnetized by a field generated by electrical energization of a surrounding drive coil, as disclosed for example in U.S. Pat. No. 2,105,479 to Hayes. The use of a plurality of such magnetostrictive rods interconnected in various arrangements are also known in the art, as disclosed for example in U.S. Pat. Nos. 3,439,199 and 3,634,742 to Bergstrand et al and Edson, respectively.
The foregoing magnetostrictive motors transform electrical power directly into mechanical linear motion. Various gearing arrangements or the like would therefore be required in order to convert such linear motion into rotary motion or angular displacement. In conventional electrodynamic motors, a rotary motion output at high torque is obtained by use of unwieldly and costly reduction gear boxes with an accompanying decrease in rotational speed. Such gear boxes are usually associated with undesirable backlash and friction, creating problems in achieving angular positioning accuracy and performance maintenance.
It is therefore an important object of the present invention to magnetostrictively transform electrical power into rotary motion at a high torque without any gear boxes and the aforementioned problems associated therewith.
Another object of the invention in accordance with the foregoing object is to more directly and efficiently convert electrical power into rotary motion at high torque levels by utilization of magnetostrictive materials.